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Does the Flight Data Recorder store the data locally or send it to an offsite backup while in flight?
I was wondering, what a black box actually does ? Does it store the in flight data, in case an accident should occur or it's sending it to an offsite backup while in flight ? And if it stores the data, how huge is it's size, cause I've heard airplanes are known to generate several terabytes of data during a flight.

Possible duplicate: https://aviation.stackexchange.com/q/1147/8730

TERRAbytes of data in a flight??? Not unless you had a huge number of high-def video cameras all running continuously. FDR’s capture a lot of data, but it isn’t near a terrabyte. They can capture & store all the flights over a week or two, which is downloaded at regular intervals by maintenance. And we aren’t talking server racks of hard drives here!

@RalphJ Well, some planes are generating 1/2 a terabyte on each flight, so at least he's in the right ballpark.  Take a look at the linked question/answer if you are curious.

@DanielKiracofe That is 10K per second, so well under 1 megabyte per minute. The trans-Pac flight of 12 hours is 720 minutes.  So well below half a GIGAbyte per flight, i.e. 200 orders of magnitude less than a TERAbyte.

@Lnafziger Looked at the linked article. While the IOT on a 787 might be generating that much data (the article was way short on specifics), nothing suggests that it is all going into the FDR. For example, data on who used which IFE channels & for how long is interesting, and exactly the sort of stuff the IOT can generate in great volume, but that wouldn’t be going into the FDR. I wouldn’t put too much stock in that 1 value mentioned without explanation in the 1 article.

@RalphJ Actually, you are correct, it says that the internet connected devices generate that much, but doesn't say that it is logged on the FDR.  Thanks!

@RalphJ, sorry I got my math wrong. you were right. I deleted my comment.


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Can an airplane flying above 35,000 feet be heard on the ground?
Can the sound produced by a commercial aircraft flying at 35000 feet be heard on the ground when the surroundings are quiet?

At what ground elevation? I think the answer is "yes" regardless, but ground elevation might make a difference. I often hear B747 and A380 aircraft flying over at those high flight levels, but an elevation of 3000 or 5000 ft is different than at sea level.

Yes
It doesn't even has to be very silent around you.
But because of the speed of sound, you will hear the aircraft later. Here is the approximate time, the sound needs to reach you:

Speed of sound at MSL: ~340m/s
35.000 ft in m: ~10660m
10660 / 340 =
~ 31s

That means you will maybe hear the aircraft but you are not going to spot it where the sound comes from.
Note that this is not an exact value, as speed of sound varies with air density and temperature, which both change the higher you are.

This appears to only address the delay in hearing the sound. Could you add something about attenuation?

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Is there any flight school that uses jets as part of their training program?
Is there any flying school out there that use "jets" as part of their training program? I mean like a Cessna Citation or Phenom.

Related

It's rare (and EXPENSIVE) but there are a few flight schools which offer primary flight training in the Embraer Phenom 100 and Citation Mistang aircraft.  Angel City Flyers in Long Beach, CA (KLGB), is one such flight school.  Bring your banker; it's going to cost $1000+ per flight hour plus fuel and instructor fees!
Another place is the National Test Pilot's School in Muroc, CA.  Their 11 month Masters of Science in Test Piloting course will make you an accredited test pilot and log flight time in over 30 aircraft, including jet fighters like the Saab 35 Drakken.  Tuition is $960,000!!!!!!

You have no idea how much I want to go to that test pilot school.

Yes, Lufthansa flight training in Bremen uses the Cessna Citation CJ1+.

D-ILHA
D-ILHB
D-ILHC
D-ILHD
D-ILHE

The KLM flight academy used to have Cessna Citations, but I think they no longer use them as part of the training.

FlightOptions at the Sunshine Coast in Australia have a Level D Citation Mustang simulator, and a real Mustang as well. The facility used to be used by Singapore Airlines for their pilot training. Great location!

The Swedish Air Force uses the Sk 60 jet (Saab 105) as its only trainer, including initial training.

The UK used to do primary training in jet provosts, but stopped due to a high accident rate.

For initial training, I don't think there is any flight school or Air Force in the world that will let you begin in a jet.
At the later stages however there are some programs that incorporate jet time. I believe Lufthansa's ab initio course uses a Citation as the final stage before joining the airline. But generally speaking most pilots in training programs don't fly jets until joining the airline.

Ever heard of the T-37 primary trainer? For decades, the standard USAF pipelne was about a dozen flights in a Cessna 172 (one solo), then on to T-37's and then T-38's.

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How are the compressor and turbine disks connected?
What is the typical way the compressor and turbine disks connected to (LP/HP) shaft ? How are the disks connected to each other  (e.g., curvic coupling, bolts or others ?)

From The Jet Engine, Rolls Royce, issue 5: a compressor drum assembly. There are holes at the lower bit which attaches to the shaft, and another section of the book mentions hundreds of holes for bolts. These holes might be for fasteners.

Typically the blades must not be too rigid but flexible. Ideally, the fir tree method is used to lock the blade root onto the disk, although there is its other counterpart.
Overall, you have the blades being attached to the disk, the disk attached to the drum and finally the drum to the spool/shaft. However, you must understand that each configuration or the methods used will vary from manufacturers to manufacturers and the type of engine under consideration. For example the centrifugal compressor and axial flow compressor. Hope this help.

This doesn't really answer the original question

In a gas turbine engine there are two types compressors and turbines*(dual spool engine)*. Overall, the compressor is connected or coupled to the turbine via a shaft. Hope this link helps https://www.mikipulley.co.jp/EN/Products/FlexibleCouplings/about.html#:~:text=A%20coupling%20is%20a%20mechanical,error%20(misalignment)%2C%20etc.

Yes but the OP question is HOW are they coupled. You just keep saying that they are coupled without giving any details.

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How to calculate the location of C.G. A.C. & N.P. in static longitudinal stability?
We are in the conceptual stage of design and, using Raymer & Nicolai as references, I am doing a rough calculation of "power off" neutral point (N.P.) to find the optimum c.g. and a.c. positions.

As seen in this photo, which is also reflected in Nicolai, when doing a static longitudinal stability analysis, the moments are summed assuming the c.g. is aft of the wing/body a.c. and the tail provides a negative moment (nose down) while the wing provides a positive moment. It assumes both tail and wing provide positive lift. I understand that in this configuration, the positive tail lift would shift the overall a.c. (neutral point) aft and the c.g. would just need to be in front of the neutral point for static stability.
However, what is confusing for me is that conventional stability usually involves placing the c.g. in front of the a.c. and n.p. so that the wing provides a negative moment (pitch down) and the tail stabilizes this by providing a negative lift (down force) to pitch the nose up. Why assume the c.g. is aft of the a.c. and the tail is providing positive lift? Why not sum the moments assuming the c.g. is in front of the a.c. for calculating neutral point?
Any help would be much appreciated, thanks!

Look here: https://aviation.stackexchange.com/questions/47306/does-static-longitudinal-stability-require-download-on-the-tail. Does this help?

Kind of. I am still confused on why static stability in two respected textbooks is analyzed assuming a positive vertical tail lift and the c.g. behind the a.c. of the wing. I understand that theoretically that configuration can be stable, but why not analyze the moments and assume the c.g. is in front of the wing a.c. like in most conventional designs?

Why assume the c.g. is aft of the a.c. and the tail is providing positive lift?

Maybe the two authors were sick and tired of that old meme that positive longitudinal stability requires negative lift on the tail. This is simply not true and never was, still it is believed like some religion.
What is true is that more static stability needs less tail lift, and many aircraft have so much stability built in that their tail lift is always negative. But with modern flight control systems this negative lift means more drag than necessary. Back in the old days, when the pilot wanted to let go of the stick or yoke in order to read a map or take a leak, a tail downforce was the best way to make sure the aircraft would behave. Still, low and sometimes missing roll stability meant that the pilot could never take his eyes off the horizon (real or artificial) for more than a short while.

Why not sum the moments assuming the c.g. is in front of the a.c. for calculating neutral point?

The position of the center of gravity relative to the wing's aerodynamic center has no significance for stability — all what counts is the center of gravity position relative to the overall aerodynamic center, fuselage and tail effects included. A smaller tail means that for the same stability the tail lift has to be lower, and most aircraft have the smallest tail surfaces that their designers could fit.

Thanks for the clarification! This is along the lines of what I suspected. So the authors' method will give you the farthest aft c.g. point to optimize drag? I guess if you really needed the design to be more stable, you could calculate N.P. assuming a negative tail lift but it would reduce maneuverability and increase drag.


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How is radar used to help aiming a gun on fighter jets?
I know gatling gun is fixed mounted to the airframe of the plane, thus cannot be rotated left/ right or up/down. However watching DCS pilots dogfighting with opponents they sometimes mention their radar is broken thus have no precision aim on the main gun.
I do not understand how can radar assist you to aim main gun, since only possible gun aim is to aim the plane's nose to the target or offset of the target. I know that fighter jets has a gun tunnel shown on a HUD and that it's up to a pilot capabilities to correctly use this feature. But if I understand the HUD gun tunnel it is just the speed, distance and G force calculation where the bullets will actually fly.

The complexity is that you're also moving, and aiming the gun will affect the trajectory of your own plane and the bullets. The bullets will also travel with inertia from your own plane, so if you were doing a steep bank, the bullets will not travel straight like in video games. If anything, I wouldn't expect a human to properly aim within any reasonable distance.

@Nelson Why would not bullets in video games follow the same rules (if simulated) of physics?

@Vladimir because it is a massive amount of work, and nobody really cares, because most people are ignorant about real firearm behaviors.

@Nelson People absolutely do care and integrating the EOMs of a single solid body is not that hard. The aerodynamics will be simplified but can be close enough.

@VladimirF You're free to add the physics simulation as a mod. Plenty of video games support mods.

If simulated. But almost invariably, they are not, at best a much-simplified form is used, and only when performance would allow. Gaming platforms don't have the overhead to simulate 100 rounds per second, in addition to the performance of much more complicated jet aircraft.

@Erin, radar does not in any way help the pilot "aim" the gun. All it is used for is to determine the range, and therefore the Tine Of Flight (TOF), which positions the gunfight along the computed stream of bullets, at the correct range in front of the muzzle. The position of that stream is calculated completely independently of the radar range, on measured shooter aircraft motion.

@CharlesBretana did I comment and delete it or something?  I don't see where I said anything to get a ping

@Erin, did you delete a comment? I don't see what I was referencing here anymore! I hope I'm not getting senile in my old age, but I could have sworn there was a comment that said that the radar is used to "aim" the gun... In any event, as I recall, what I pinged was the comment, and I don't see it anymore either... where is it?

F-16 engineer here.
This is from a great article about fire-control radar in fighter jets:

For guns kills, if the aircraft has a radar lock on a target, it can
accurately gauge range to the target, and provide the pilot with the
appropriate corrections for lead and gravity drop, to get an accurate
gun kill.  Without the radar, the pilot simply has to rely on his or
her own judgement.

(migflug.com)
Without radar lock, you won't get all the nice information to help get the best shot possible.
Such as the offset target on your HUD that you mention.
You can compare it to fire-control systems on anti-air ship cannons. It's far easier to hit a moving target far away if you know its direction and speed, and way quicker if you let a computer do all the calculation.

Welcome to Av.SE!

Welcome to Aviation.stackexchange!

You mean bullets don't travel in straight lines at infinite speed like in video games?!

@RalphJ & DeltaLima Thank you for the welcome!

@DKNguyen If you turn up the bullet speed knob they will eventually behave just like in video games! Only problem is they'll be flying so fast that impact won't be registrered, and then promptly ignored! /s

@DKNguyen Which video game in particular has such bullets? I am not aware of any. (But stay in this century please, if not this decade.)

@VladimirF the term you're looking for is hitscan.  Still used in Overwatch and CoD to my incredibly limited research.

On minor correction. In air-to-air gunnery, there is no "Gravity Drop". What we might assume is gravity drop is automatically taken care of by what engineers call  Lead for target acceleration. If the target is at zero "G", then the target "falls" exactly the same amount during the bullet time of flight (TOF) as the bullets, so if the system corrects for the Gs that the target is under, it will automatically be correcting for bullet drop.

@foreverska OK, I thought we were discussing avioton and hence flight simulators. All I remember (and I mainly played games in the 1990s), had bullets visibly flying from the shooting plane, no instant hits at all. I do not have any illusions about them being too precise back then but today they behave very realistically in flight simulators.

@VladimirF Most games with guns use either completely 'hitscan' as the kids call it these days (e.g. infinite speed, straight lines), or a combination of hitscan weapons with some physics-based weapons (e.g. calculating a projectile flight path and flight time). Some FPSes are starting to focus more on physics-based ones as computers get more powerful and as a function of their design/appeal (e.g. ArmA, Battlefield), but they're in the vast minority compared to "all games with guns".

@TylerH Well, OK then, but what have FPSes have to do with aviation? There were tracer bullets flying visible in the flight simulators already in the 1990s. Surely with simplified trajectories, but now in 2020s they must be much more precise. I know I wrote name one videogame, but I think at this venue the aviation topic can be understood implicitly.

@VladimirF You're the one who asked about video games...

@VladimirF I literally just quoted one of your comments from 2017 like half an hour ago o_O and now i see you here as well. Very cool indeed!

@TylerH OK, I thought we were discussing aviation and hence flight simulators... I do agree FPS is video game but it's not flight sim.

@Skye-AT Seems an odd context to assume, since flight sim games typically don't have bullets or even combat in general... they have flying. At least the two main ones, Microsoft Flight Simulator and X-Plane, don't (aside from little one-off mods).

@TylerH DCS world...

There are three components to an air-to-air gun solution, that must be taken into consideration by the engineers designing the gunsight mechanics, and well understood by the pilot utilizing the system.

Lead for Target Motion or Velocity Lead (Lm). This is the same thing as is utilized by a skeet shooter. You must aim the barrel of the gun where the target will be when the bullets get there, not where it is now. You cannot just point the gun at the target. You must point it some angle in front of the target in the direction the target is moving in your field of view. Lm always lies in the target's plane of motion. This requires that the system know the time of flight (TOF) of the bullets, and the Line-of-sight rate (LOS) of the target (how fast is it drifting across the inertial background in your field of view. If the target is moving at 20 degrees per second, and, based on the range, the TOF is 1.5 seconds, then you must aim 30 degrees in front pf the target, along it's projected velocity vector. Fighter pilots use a radar lock on to determine the range and TOF, and when there is no radar lock, gunsights assume a default range (in the F-4 it was 1000 feet) . The target LOS is determined by the gunsight by assuming that if the pilot is "tracking" the target, the shooter aircraft turn rate must be identical to the target's LOS. When the pilot is not tracking the target (as in a highly dynamic close range, high angle shot (called a snap shot), the pilot must understand this effect in order to turn on the gun with an additional lead angle to compensate for the target's relative motion in the windscreen. Effectively he pulls the trigger when the target, moving towards the gunsight aiming reference, appears to be about to cross that aiming reference about a second or two in the future.

Lead for Target Acceleration or Acceleration Lead (La). If the target was at zero Gs, (in ballistic free fall), there would be no need for La. Only Lead for target motion and Drag shift would be required.  La is required when the target is turning away from the ballistic path that the gunsight would be predicting without La. La always lies in the target's plane of acceleration (the plane the target aircraft is accelerating in (normally defined by where the lift vector or vertical stabilizer points). The gunsight assumes that the target Plane of motion is the same as the shooter plane of motion, and that the the target G-load is the same as the shooter G-Load. The solution is based on the assumption that the target is accelerating or pulling Gs towards the shooter, and that the shooter, to match the target's turn rate, is pulling the same amount of Gs in the same direction. This is normally close to accurate when the target is at low angle off relative to the shooter, but is not accurate at higher angle off.

The last component is the correction for what is called Drag Shift. Bullets slow down after they leave the muzzle. This slowing causes the bullets to drift aft of their original line of fire (Line of departure or LOD). Imagine the top turret on a B-17 firing forward and upwards at a head-on approaching target. If the bullets maintained a constant velocity after they left the muzzle, all that would be necessary s to point the guns where the target will be one TOF from trigger squeeze (La), and correct for 1 G target acceleration (La). But the bullets slow down. That means it will take a slight bit longer to get out there, and the target will drift further aft in that small amount of time. Therefore, the gunner must aim slightly lower in elevation (less lead), to compensate for that. Imagine a high pressure water hose, forwards and upwards out of the sunroof of your SUV at 80 mph. The stream of water will appear to curve and bend backwards relative to the vehicle, the further it is from the nozzle. If you were trying to hit a drone flying 15 feet above you and 15 feet in front of you, you would have to aim in front of him to compensate for the apparent rearwards drift of the stream of water. This correction is required whenever the gun firing line is not aligned with the shooter aircraft velocity vector through the air. For a fighter, since guns are must be in lead, this means it reduces the the lead required by a small amount in the plane of target motion.

The relative contribution to the  total gunsight solution from these three components, generally, is as follows:

Lead for target motion:        70-85%

Lead for target acceleration:  10-25%

Drag Shift:                    5-10%

On the JA37D, it would auto-steer

On the D-version of the fighter variant of the Saab 37 Viggen, it would help in steering
The last version of the fighter variant of Viggen had an auto-steer mode, where the "steering automat" would give yaw and pitch corrections to aid in firing the cannon. This was — of course — dependent on data from the radar.
NOTE: Since the Saab Gripen is even more advanced than the Viggen, it would surprise me greatly if the descendant did not get the same thing.

Imagine your radar suddenly locks a bird or wingman. Hope the system isn't very .. abrupt.

@Devilscomrade It is not all hands off, so — no — that is not how it happens. I have the flight manual in Swedish but it is hell trying to translate it. Just rest assured that this is not any kind of Rabid Terminator Mode. :)

A lot of Swedish kit was designed for operation by reservists, I wonder if this is an example (do/did they let reservists fly fast jets, I wonder).

@Rich You are thinking of conscripts. Pilots/aviators are commissioned officers. There are reservist pilots too (which was part reason of the 2005 JAS-39 Gripen crash).

Ah, do they not have conscript officers in Sweden, like in Switzerland? I was really thinking of conscript/reservist as meaning not a fulltime career officer.

This meant the radar would give correction to aim the plane at the target, thus aiming the gun?

@totalMongot In effect, yes.

In reviewing the book titled "Fighter Pilot Gunnery" from 1943, it is critical for a fighter pilot to know his own air speed, the bullet velocity, and the speed, direction, and range to the target. With this information, the pilot can aim the plane to where the bullet and the target will intersect. With radar, the target information is essentially a known vice a guestimate and a fire control computer can calculate the aim point and display it on the HUD.

Most aircraft guns are not radar guided (except [CIWS systems] on naval vessels1). Fighters use HUD or illuminated visual reference, because the range of typical cannon rounds is insufficient compared to a missile; radar makes little practical use.
However in the 60's/70's B-52 bombers had a tail gun with an M61 cannon and radar aperature.
A 20x102mm round has an effective firing range of 2000 feet. With deviations of a moving target, filling the sky with lead in a general direction is more important than dead on sniper like accuracy.
Visual synchronicity is achieved by having the gun sights to the pilot offset to the position of the gun (Often below the pilot) so it's angled at a set of degrees past a given range, a fighter pilot knows the gun is useless past "X" amount of feet thus wouldn't even fire. Radar is used to determine general threats before engagement and seeking of potential targets as well as navigation.

"filling the sky with lead in a general direction is more important than dead on sniper like accuracy." Yeah... but also the rate of fire is so high that ammo must be used wisely because it doesn't last long. Once you're at gun range it can be harder to safely disengage, also. I would err on the side of being in a control position and waiting for the target to lose speed and therefore turn rate to try to have an easier firing solution versus "filling the sky with lead" and hoping something hits. Total firing time of an F-16 gun is five seconds worth of ammo.

And the dispersion of the M-61 A1 Gatling gun (on almost all U.S. Fighter aircraft), is about 6-8 milliradians. (that's about half of one degree). That means that 1000 feet in front of the gun, 80% of the bullets lie within a 6-8 foot circle. The wingspan of a typical adversary fighter aircraft is 45 - 60 feet.  If you fire a 50 round burst, the bullet density will be about 1 bullet in every 3 square feet of that 7 foot circle. So yes "fill the sky with lead"?

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authors: Vladimir F Героям слава


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Modeling of the aerodynamic characteristics of the wing
As a part of the engineering thesis I work on the methods of modeling of aerodynamic characteristics of wing. In it, I rise an issue related to the impact of changes of aircraft attitude during maneuvers, I mean when there are angular rates like roll and yaw rate.
Now I'm looking for the methods which will be able to describe the spanwise change of lift and drag coefficiens during such maneuvers from the simplest ones to most advanced. So far I have considered so-called strip theory (when wing is discretized into independent strips and e.g. during positive roll rate there is increase of AoA along right wing and decrase on left one, so it causes appropriate change of lift, induced drag and profile drag) and Vortex Lattice Method. I know that in VLM I have to add aircraft angulara velocity because basic describtion of this method take into account just freestrem velocity caused by aircraft translation. I also think to analyse CFD method to estime wing characteristics in motion.
Hence my question, are there maybe other methods which estimate/model wing aerodynamic characteristics that I can consider? If there are methods which also describe the spanwise stall situation , I would be very grateful? Would you recomend any literature or articles related to above problem.

May be of interest A review of aerodynamic flow models, solution methods and solvers from Delft TU, and the High fidelity large eddy simulations from Onera.

The answer depends on what you have access to. The most capable software for modelling the moving airplane is proprietary and very expensive to acquire. On the other hand, vortex lattice methods already give good results within the realm of attached flow and should be accessible at your university.


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Why would I want to lower the stall speed?
Why would a cargo pilot for example want to dump fuel to lower the stall speed? I understand that lowering the weight decreases the stall speed, meaning it is "easier" for the plane to reach this new lower speed and stall, correct? Why would I want that? Don't I want to have a higher stall speed so I could be far from stalling? What am I missing here.

A higher stall speed would mean you're closer to stalling because there's a smaller margin between the maximum speed (VNE) of the aircraft and the stall speed.

" I understand that lowering the weight decreases the stall speed, meaning it is "easier" for the plane to reach this new lower speed and stall, correct? " -- not correct

Are you aware that the stall speed is the minimum speed, not the maximum?

STALL SPEED MORE = YOU HAVE TO FLY FASTER TO STAY AFLOAT.

It’s only easier to reach the lower stall speed if you’re starting from 0 (dead stop).  If you’re already flying at given airspeed X, the distance from X to the new lower stall speed is greater, making it harder to stall.

Don't I want to have a higher stall speed so I could be far from stalling?

Unfortunately this is incorrect. Aerodynamic stalls happen when an aircraft’s airspeed is at or below the aircraft’s stall speed for a specific configuration, attitude, phase and condition of flight. A higher stall speed will mean that you will be closer to stalling at any given airspeed. A lower stall speed is desired so that you can maintain a safety margin between your airspeed and the stall speed.
A lower stall speed also means the aircraft can fly and land at a lower airspeed and, in turn, ground speed. This would decrease its momentum, its required landing distance, and (in case of a soft field landing, off airport landing, or crash) its impact force with the ground.

“I understand that lowering the weight decreases the stall speed, meaning it is "easier" for the plane to reach this new lower speed and stall, correct?”

Unfortunately, the second half of this statement is incorrect. The different weight will produce different momentum, and a different amount of force required to change velocity. That does not mean that it will be easier or harder to reach a stall speed with a greater difference from the original flight speed than you would have had with the original stall speed. It just means that you may have to have a greater amount of acceleration to reach the lower speed than you would the higher speed in the same amount of time.
This is all irrelevant, though, since the entire point of lowering the stall speed is to make it harder to stall the aircraft. Especially at your given airspeed. Which means that they aircraft can fly at a lower airspeed without stalling. You do not want to stall the aircraft. This is important during low speed maneuvers such as approach, landing, and turns to final.
To put it in laymen’s terms, the stall speed is the airspeed at which the aircraft would stop flying. Another way to say it is that it is the airspeed at which the wings stop producing lift (or enough lift to keep flying). In reality, the stall speed is the airspeed at which flying straight and level would produce a high enough Angle of Attack that the airflow would separate from the wing surface. This is called the Critical Angle of Attack. Although it can be different for each aircraft, it is generally about roughly 17°. It also does not change for a specific aircraft in its configuration.
Lift is a function of: wing shape; airspeed; and the angle between the line formed by the relative wind and the chord line of the wing (Angle of Attack). Altering any of these would alter the amount of lift produced.

You alter wing shape with the wing control surfaces. The more camber you have, the more lift you will have.
You alter airspeed with power and pitch. The more airspeed you have, the more lift you will have
You alter AoA with wing load. The higher the AoA, the more lift you will have until it reaches the Critical AoA. The more wing load you have due to the forces applied on the aircraft’s mass (such as gravity and g-forces from turns and acceleration/deceleration), the more lift you will need to have to counter the wing load. And, the higher the AoA will need to be in order to produce enough lift to counter the wing load.

Reducing the weight which the wings have to carry (wing load) would reduce the amount of lift that must be produced. Reducing the wing load reduces the AoA that must be maintained to produce lift. The further away from the Critical AoA, the better and safer flight will be. The further away from the Critical AoA, the further you are away from a stall.
In the particular scenario brought by the Original Poster, this all may also be irrelevant. As pointed out by @Peter Kampf, dumping fuel to reduce weight may just be for the purpose of getting the aircraft below its Max Landing Weight. Or, in the case of an emergency landing, ridding the aircraft of as much flammable material as possible in case of a crash.

Yeah, it's weird.  Airplanes can land overweight, just need a more complex after-incident inspection.  If I dumped 500 gallons of kerosene in a lake, and I told the authorities I did it to make a future inspection easier, I'd be in big trouble LOL!

@Harper-ReinstateMonica: If you dump from high enough, it mostly evaporates on the way down, doesn't it?  Unlike dumping "in a lake" where it's likely to to cause a localized problem.  (At flight speed, the amount of fuel per volume of air is not huge, and it has thousands of feet to rain down.)  Or am I mistaken, and this does lead to a rain of kerosene under the flight path?  It's still a lot more spread out than most ground-based dumping, and I'm not sure what the authorities would have to say if you arranged to sprinkle kerosene into the wind from a tall radio mast by the lake...

Dumping fuel on an elementary school is never a good look:  https://www.latimes.com/california/story/2020-01-14/plane-dumps-fuel-on-students-on-school-playground-en-route-to-lax-officials-say


text:
How to leverage Lynx NGT-9000's integrated GPS/WAAS?
I’m inheriting an IFR capable 1964 Cherokee 235 that is not equipped with a GPS. I’m looking at installing a Lynx NGT-9000 to get ADS-B compliant and gain the traffic and weather information.
Is there any way to leverage its integrated GPS/WAAS to enable LP/LPV approaches and file IFR direct? I don’t want to over panel this plane.

I feel this pain after I just dropped a substantial amount of cash Garminizing a 1965 Cherokee 180 just so I could fly GPS approaches. ADS-B Out is cheap, but a GPS I can use as a pilot is still hideously expensive :(

Sorry, but windmills approach certified GPS systems do not work that way: A GPS approved for IFR navigation and approaches, like a Garmin 430W or GTN650 or an Avidyne IFD440, are more than just an approved position source such as what's included in the NGT-9000 transponder. They have an approved navigation database and interface with (or provide the equivalent of) a Course Deviation Indicator (CDI).
You can't just suck position data out of the NGT-9000 and fly around using it because while that device has an approved high-quality position source it doesn't have an IFR-approved navigation database, so there's no way to take that GPS data (your position as a point in space) and relate it to known waypoints (VORs, NDBs, airports, intersections, etc.) in a way the FAA considers satisfactory as a primary means of navigation.
You can take the GPS data from it and interface it with an iPad - Foreflight speaks the Lynx L3 language - to use for enhanced situational awareness, which is a huge win, but that's not enough to get you to file GPS flight plans: You would be limited to filing flight plans based on your other installed primary navigation instruments (VOR, ADF, DME).

Why isn't there a gadget that can "overlay" an ADS-B position source and provide GPS navigation using that?

@UnrecognizedFallingObject Mainly because as far as I'm aware nobody has built and certified one yet, and they'd have to get it approved to interface with each ADS-B position source (assuming they expose the position and integrity data over a hard-wired interface). At that point you're basically building a GTN625 (GPS navigator only) equivalent but with the GPS module external - Garmin retails those for only $2000 less than the full GTN650 (GPS/Nav/Com) and maybe cut another $2k out for the GPS, but you lose a lot of functionality so I'm not sure there'd be a huge market for them.


text:
Are aviation accident investigation reports always made public?
How is the dissemination of aviation accident investigation reports regulated? Are the reports public by default, or can they be kept secret? Are there any known rules on this?
If the reports are not public, do the people involved in the accident have a right to access the evidence and/or the reports? Can they find out what the verdict (if there is one) was?
This surely depends very much on the country. Please indicate the regional scope of your answers. (My interest is specific but not limited to France.)

In the US:  http://www.ntsb.gov/_layouts/ntsb.aviation/index.aspx

Unless there is some risk of national security to releasing a public report of the accident, the reports are released. You can search the public ones (almost all are public) at the BEA website. The same applies for the other aviation accident and incident reports and you can find the available reports on the websites of the group that has jurisdiction over the accident/incident; NTSB for the US, AAIB for the UK, and many other ones.

This is a complicated answer, and yes, it is very dependent on country and even the type of accident.
First, be aware that there can also be a big difference in "incident" vs "accident", and they may be reported differently.
Next, each country has its own laws and regulations about the dissemination of materials generated by government entities. I don't know French law or it's rules for releasing records, so I would have to defer to somebody familiar with it. In the United States we have the Freedom of Information Act which regulates how documents are released, exemptions from release, and a request process.
Again, I'm not sure about the French, but in the U.S. we have something called Procedural Due Process which allows both sides of the proceedings equal access to evidence. This comes from Due Process and by extension, the Magna Carta. Really now we are getting into the rights and obligations under law and is a bit outside the scope of this site. Point is, at least in the U.S. a person in a civil or criminal lawsuit has the right to examine the evidence as equally as the prosecuting party.
Now, as far as current access to records... This is a digital age, everything is done on computers, fed to servers, and can easily be made available to the general public, usually if it is in the public interest. 1989 was a different story. The first "laptop's" weren't introduced until the 80's and ones that would run word processing software weren't readily available (or very affordable). Most investigators at that time would take notes on paper then go back to an office and type them up (on a typewriter mind you). These reports would then be given to others in the organization and filed.
The U.S. has done a pretty damn good job of digitizing old reports and it may be that the French have not have bothered to put the resources into digitizing these reports. If your search for information is purely "on the web", you may need to actually visit a library (national) or make a request to the investigating agency.

and even if the report itself is released, portions of it may be withheld from the public for various reasons, from national security to privacy concerns and fears that people might go vigilante and try to kill named persons.

Is procedural  due process actually relevant? An NTSB investigation is not a criminal investigation and its findings cannot be used in a court of law.

@DavidRicherby -- the conclusions cannot be, but AFAIU (IANAL tho, may have to bring this up with the legal eagles @ work) the factual findings of an NTSB investigation are admissible in court -- if they weren't, it'd make life really screwy for the DOJ if they had to prosecute someone for say intentionally sabotaging an aircraft.

BTW: while the NTSB has done a fairly good job digitizing old reports, there are still quite a few that aren't available on their website. ERAU's library has gone through and digitized all the old NTSB aviation accident reports, though.  (Now, if only someone'd do that for the other modes!)

@UnrecognizedFallingObject It appears that you're right that findings of fact can be used in a criminal trial. It turns out that even they can't be used in a civil trial, though: the reports themselves say, "The Independent Safety Board Act, as codified at 49 U.S.C. Section 1154(b), precludes the admission into evidence or use of Board reports related to an incident or accident in a civil action for damages resulting from a matter mentioned in the report."

@UnrecognizedFallingObject I was thinking of the UK Marine Accident Investigation Branch reports, which state, "This report is not written with litigation in mind and, pursuant to Regulation 14(14) of the Merchant  Shipping  (Accident  Reporting  and  Investigation)  Regulations  2012,  shall  be inadmissible in any judicial proceedings whose purpose, or one of whose purposes is to attribute or apportion liability or blame." UK Air Accident Investigation Branch reports merely say that it is "inappropriate" to use their reports "to assign fault or blame or determine liability"

@bogl Being unaware of your surroundings does not excuse an action. "Well I was unaware of the stop sign"... In Latin (law) this is called "Ignorantia juris non excusat", but either way he was "blamed" for it, but not prosecuted. The fault could not be placed with the landing aircraft, it had to go somewhere...

Without a published report it would be hard to come to that conclusion. I would not rely on Ockels autobiography alone in that regard since his view is extremely biased.

I didn't blame him, you did: "I am looking into a case some 25 years ago where the report was never published. One pilot got all the blame," from this comment. I only said that "and the "blame" may just be faulting the pilot on the ground." I was not blaming him, I was responding to you saying blame was placed with one pilot and identifying the possible source of that "blame".

USA
The public availability of information is regulated in 49 CFR Part 801:
[TBD: insert here a summary of relevant parts of this regulation ]
European Union
Dissemination of investigation reports is regulated through Regulation (EU) No 996/2010.
According to this document,

the investigation reports are to be made public ("in shortest possible time and if possible within 12 months")
the following information shall not be made available (shortened - see Reg. 996/2010 Art 14 for complete text):

statements taken from persons
records revealing the identity of persons
information of particularly sensitive and personal nature
material subsequently produced during the course of the investigation
information and evidence provided by other countries
draft, preliminary, or interim reports or statements
cockpit voice and image recordings
communications between persons involved in the operation of the aircraft
recordings and transcripts from air traffic control
covering letters and occurrence reports

the regulation shall not apply for accidents and incidents which involve aircraft engaged in military, customs, police or similar services, except when the Member State concerned so determines. (Art. 3.3)
the question of guilt is not in the scope of the accident report. Therefore the dissemination of a verdict is not covered by this regulation.

France
BEA states on its website:
"European Regulation European regulation n°996/2010 specifies that the BEA makes public information on the progress of its investigations and that it informs in advance the members of the families of victims.
In the context of an investigation that it conducts after an aviation disaster, the BEA:

Communicates through various means (internet site, press releases, and press conferences) at each major stage of its investigations (initiation of the investigation, information, interim report, and final report) to the media and the public.
Regularly sends mail to the families of victims providing updates on the progress of the investigation and gives them first access to reports to be published. "

https://www.eurocontrol.int/download/publication/node-field_download-4867-0 gives a lot of information about national differences within the EU.


text:
What is the legal altitude to fly through Yosemite Valley (US)?
I have a question regarding flying in the Yosemite Valley national park, which I flew over last weekend in an open-cockpit gyroplane.
The sectional states you must be a minimum of 2,000 ft about the highest point within 2,000 feet of you. The famous valley itself, containing El Capitan and Half Dome, has a highest point of 8,800ft or so, so when I flew it, I was at well over 10,000 ft.
However, it occurred to me afterwards, that if the valley is actually more than 4,000 ft wide (which it is), then all I needed to do was to be sure I was more than 2,000 ft above the valley floor, which is at 4,000ft.
So instead of flying over it at 10,000, I could do it at 6,000ft if I'm in the middle of the valley.
This would put me way below the peaks of El Cap and Half Dome, but provided I'm more than 2,000ft away from them, I'd be legal.
Is that correct?

I think this question can be more generalized as "Can I fly below the heights of mountains if I am more than 2,000 feet away from them?"

@SMSvonderTann No, it cannot. Most mountainous areas have no special altitude or ground separation requirements under VFR.

Short answer: you can fly in Yosemite Valley at 500ft AGL (most likely); there's no special regulation applicable there; the wording on the sectional is a non-regulatory 'encouragement' only.

By regulation, the minimum altitudes under VFR are in 14 CFR 19.119:

(a) Anywhere. An altitude allowing, if a power unit fails, an
  emergency landing without undue hazard to persons or property on the
  surface.
(b) Over congested areas. Over any congested area of a city, town,
  or settlement, or over any open air assembly of persons, an altitude
  of 1,000 feet above the highest obstacle within a horizontal radius of
  2,000 feet of the aircraft.
(c) Over other than congested areas. An altitude of 500 feet above
  the surface, except over open water or sparsely populated areas. In
  those cases, the aircraft may not be operated closer than 500 feet to
  any person, vessel, vehicle, or structure.

I don't know what Yosemite Valley looks like and whether it's "congested" or not (see this question), but it's very likely that you could operate legally at 500ft AGL there, if not lower.
What the sectional says comes from AC 91-36, Visual Flight Rules (VFR) Flight Near Noise-Sensitive Areas. But as the AC itself says, it only encourages pilots to fly above 2000ft AGL (emphasis mine):

This Advisory Circular (AC) encourages pilots making VFR flights near
  noise sensitive areas to fly at altitudes higher than the minimum
  permitted by regulation

If you read the whole thing, you can see the not-so-hidden message:

The Federal Aviation Administration (FAA) receives complaints
  concerning low flying aircraft over noise sensitive areas such as
  National Parks, National Wildlife Refuges, Waterfowl Production Areas
  and Wilderness Areas. Congress addressed aircraft flights over Grand
  Canyon National Park in
  Public Law 100-91 and commercial air tour operations over other units
  of the National Park System (and tribal lands within or abutting such
  units) in the National Parks Air Tour Management Act of 2000.
[...]
Adherence to these practices is a practical indication of pilot
  concern for the environment, which will build support for aviation and
  alleviate the need for any additional statutory or regulatory actions.

In other words, 'please be responsible and considerate because if you aren't, Congress might force us to introduce more regulations like we had to do with the Grand Canyon'. Practically speaking, I guess that if you fly down Yosemite Valley at 500ft AGL every day, even if it's completely legal you can still expect a call from the FAA asking why you're doing it and 'encouraging' you ("cough 91.13 cough") to fly higher for 'safety' reasons.

I can't provide a reference at the moment, but I believe that there is a regulation by another government entity that does prohibit low altitude flight. I understand that the FAA's recommendations are an encouragement to follow these other regulations that fall outside their jurisdiction.

@JonathanWalters It would be great if you can find it, I don't remember it coming up on the site yet

I think parts of Yosemite Valley would qualify as congested and/or settlement, given all of the campgrounds and parking lots.  And common sense tells me that going through there at 500 ft would get you a terrific amount of unwanted attention regardless.

Look here at 7-4-6 (3)(c) nearly at the bottom of the page: "Federal statutes prohibit certain types of flight activity..." Sorry, I'm not in a great spot for further digging just now.

See also the (as possibly relevant) "The National Parks Overflight Act of 1987"

@JonathanWalters I had a quick look, but I still don't see any actual regulations. The AIM says "pilots are requested to", and the Act you mentioned appears to only have required a study to identify a reasonable minimum altitude, it didn't actually create any regulations. AOPA's information says 2000' is voluntary but obviously highly recommended.

@Pondlife yeah, I agree; I think I was probably mistaken in my understanding.

@jonathan I also found this in the AIM (7-4-6(c)): (paraphrased for length) Federal statutes prohibit certain types of flight activity and/or provide altitude restrictions over designated...Parks... These designated areas, for example: Yosemite National Park... are charted on Sectional Charts.  This suggests that these Sectional markings come from a federal statute, but I still haven't located one.

@JonathanWalters I think the "statutes" refers to 49 USC 40128, which applies to commercial air tours only. It seems to give the FAA and NPS the authority to create requirements for air tours over individual parks, but it doesn't define any general minimum altitude.

(Edit: removed text about "legality") Flying "down into the valley" (even if laterally separated from all sides by more than 2000 feet, and remaining more than 2000 feet above the surface) goes against the FAA's suggested altitude when "overflying a national park", with this paragraph from AC 91-36:

For the purpose of this AC, the ground level of noise-sensitive areas is defined to include the highest terrain within 2,000 feet AGL laterally of the route of flight, or the uppermost rim of a canyon or valley.

The FAA requests and recommends that pilots stay 2000 feet above the "upper most rim of the valley". However, as others have said, this is just an "advisory" circular, and not a legal requirement.

AC's are advisory in nature, not like FAR's which have legal ramifications. AC's are FAA's recommendation, not necessarily defining legal/illegal. I'm not sure if this AC clarifies an FAR or not, I didn't see an FAR reference in the AC.

This does not provide an answer on the legality in question. As has already been pointed out, ACs are advisory only.

Yep, good catch on "legality" - this is just an AC.  Public Law 100-91 (1987) mandated the study of NPS overflights, and also specified that flights in Yosemite Valley were illegal during the study period. But that period is over, and I don't know of any specific law or FAR applying to any NPS other than the Grand Canyon.

Appreciate the thought into this. Seems like the consensus is that the AC (not a legal requirement) adds the "uppermost rim of valley" restriction but that's not on the sectional and because the AC is not a legal thing anyway, it's just a request. So I COULD do it, but I shouldn't if there's a risk of causing significant annoyance to park users.

Browsing through the Soutwest Chart Supplement I ran across this:
SPECIAL NOTICES
YOSEMITE NATIONAL PARK
Public law prohibits flight of VFR helicopters or fixed-wing acft below 2000 feet above the surface of Yosemite National Park. “Surface” refers to the highest terrain within the park within 2000 feet laterally of the route of flight or, within the Yosemite Valley, the uppermost rim of the valley.
I don’t know which public law they are referring to.

It seems to refer to PL100-91, which did ban flight below 2000' but only "During the study and review periods provided in subsection (c)", in other words, it was temporary as part of the study. Interestingly, this article shows that the restriction was actually printed on the sectional at one point, but it's now gone (if skyvector.com is current).

It's in the Supplemental now.  But "Yosemite Valley" does not appear to incude Half Dome - if you visit the Yosemite Park site and view its maps, you will see that the valley is a much smaller subset including Yosemite Village but not extending to Half Dome (nor El Capitan to the NW either).  This would seem to mean then that the "2,000 above, 2,000 away from" stipulation would apply, but not the "upper rim".
Yosemite:
https://www.nps.gov/npgallery/GetAsset/27d2a40e-1e0a-4148-b7fb-a82191fc67b3/ProxyHiRes
Google:
https://www.google.ca/maps/place/Yosemite+Valley,+CA+95389,+USA


text:
How does the Boeing 787's Cabin Air Compressor work？
How does it work in normal, overheat and over-pressure conditions? What is the function of the variable diffuser actuator?


text:
Why does the Boeing 787 use Cabin Air Compressors (CACs)?
What are the advantages of this new air conditioning system compared with the traditional engine bleed systems? More engine output power, or easier adaption to future aircraft design?

In addition of the answers, there is a general trend towards more electric aircraft ("MEA") with savings in mass, fuel, complexity and gains in reliability.

According to this paper from Boeing its CAC is simply more efficient than the old style bleed-air designs and reduces fuel usage.

In the no-bleed architecture, electrically driven compressors provide
  the cabin pressurization function, with fresh air brought onboard via
  dedicated cabin air inlets. This approach is significantly more
  efficient than the traditional bleed system because it avoids
  excessive energy extraction from engines with the associated energy
  waste by pre-coolers and modulating valves. There is no need to
  regulate down the supplied compressed air. Instead, the compressed air
  is produced by adjustable speed motor compressors at the required
  pressure without significant energy waste. That results in significant
  improvements in engine fuel consumption.

Boeing lists the reasons/advantages for the move to electrical systems here.

Improved fuel consumption, due to a more efficient secondary power
  extraction, transfer, and usage.
Reduced maintenance costs, due to elimination of the
  maintenance-intensive bleed system.
Improved reliability due to the use of modern power electronics and
  fewer components in the engine installation.
Expanded range and reduced fuel consumption due to lower overall
  weight.
Reduced maintenance costs and improved reliability because the
  architecture uses fewer parts than previous systems.


text:
How fast were propeller planes during landing on aircraft carriers during WW2?
I have seen reports of up to 90mph but that seems high?

The F4U Corsair had a stall speed of 89mph, so landings were probably carried out well above 90.

Is it relative to the Carrier or air?

@Ling stall speed always related to air. If you have a moving carrier you make it easier for the pilot.

@vasin1987 Yes, but OP didn't ask about stall speed. Maybe he thinks 90mph is high relative to the carrier.

The stall speed of the F4U Corsair may be 89mph, and a safe approach speed might be 95-100mph, but that's airspeed... Measured with reference to the carrier deck, you have to substract 20mph headwind (nothing unusual at sea) and also around 30 mph of the carrier own speed. Hence, that plane touched down at a sedate 45-50 mph, with respect to the carrier deck...

It depends on the aircraft, but here's an example.
Consider the stall speed of the Grumman F6F Hellcat

Landing condition-power on - MPH 78.5
  Landing condition-power off  - MPH 86.0

According to this checklist, your abeam speed was 75 knots, once in landing configuration.
You'd want your approach speed to be above the stall threshold, which 75 knots is. Convert 75 knots to mph and you get 86 MPH.  That's a tighter performance margin than typical approach speeds now which are typically 1.3 x stall speed.   Each aircraft has its own performance margins.  90 MPH translates to about 78 knots which looks like a reasonable figure, depending on the type.
The F4U Corsair had similar performance.

Stall speed:
  Landing condition - power on - MPH 74.5

The carrier will typically try to recover with about 25-30 knots of wind down the deck, which (by turning into the wind) will be a combination of the speed of the wind that day and the ship's speed.  (We  nautical types use knots, not MPH).
Subtract wind over the deck from the approach speed and you get "how fast over the deck" the aircraft is traveling as it touches down.
For a very similar configuration, here is a T-28C carrier approach and landing video.  The T-28C is basically an updated WW II fighter/bomber used as a trainer. (I got my initial training in a T-28B.  The C's were out of use by the time I got to flight school).

Do you also know the speed of the carrier? It would of course be going at full speed to reduce the relative speed which matters for stopping.

(WP says 32.5 knots maximum for Yorktown-class)

@Jan it's irrelevant in terms of the aircraft air speed, how fast the carrier is going won't change your stall speed, nor your approach speed.  It will influence the relative motion and the final ground speed on touchdown (and thus runout, etc).

I didn't say it's relevant for air speed. It is not. But it is relevant for "ground" speed, and the question does not specify "air", so it might mean either.

@JanHudec I understand, your point, but the carrier doesn't travel at a fixed speed.  What it tries to do is achieve a particular relative wind ...


text:
How far from the runway should a small plane start its descent from 5000ft?
I don't fly, don't have a clue. But one of the main characters in my book DOES: it's a Cessna 152, just him at 14 stone and a couple of small bags, all conditions are perfect and he's flown from about 140 NM away. Would 5000ft be about the right altitude?
The question is: how far away is the runway (a grass one on an unlicensed airfield) when he starts his descent? It's a direct approach, no pattern.

Have a look at this question/answer. It should be enough to get you in an acceptable range.

Also, regarding altitude, see this question, it would depend on the direction of flight and if they are VFR or IFR.

I applaud you for asking. I've been reading the Dirk Pitt novels by Clive Cussler, and his descriptions of flying have a tenuous grasp on reality, based on what I've learned here, and it's rather distracting.

Regarding whether the cruising altitude is appropriate, assuming he's flying VFR (Visual Flight Rules), he should be at an odd thousand plus 500 ft for east headings (360-179 degrees) or an even thousand plus 500 ft for west headings (180-359 degrees). Also, you didn't specify a field elevation.

For a comfortable decent you generally want to come down at 500 Ft/Min on the Vertical speed indicator. The 152 is doing about 95Kts over the ground (assuming no wind). So you are covering about 1.5 miles a minute to round it off. So you need to drop 5000 ft on your approach to the area. At a comfortable rate that will take about 10 minutes. In that time, covering 1.5 miles a minute, you will need to start your decent about 15 nautical miles out.

While this method of calculation does apply towards answering this question, your answer does not. The question specifies a straight in approach with no pattern flown, thus the descent is to be made to the field elevation. A more correct answer would be about 15 NM, which is true either for a 3° descent path, or for your calculation method.

I must have overlooked that last sentence. I have corrected as such.

Thank you guys SOO much! I've used the advice and finally got the character down realistically. His next flight to same airfield is in hot summer months and it's on the east coast so maybe he'll come in from over the sea to avoid thermals from land. Realistic scenario for experienced pilot? Thanks again, you've been quick and really helpful.

@NathanKStrawn that really depends on the airport but generally speaking you can come in from over water. However you are limited as to how far out over the water you can fly here in the US due to the ADIZ which you dont really cross unless you are leaving the country.

@NathanKStrawn However most pilots generally avoid flying over open water if they can help it. There is no reason, and perhaps an increased risk to go out over water if you can get to where you need to be over land only.

Worth knowing, many thanks!

The standard 3° glide path works out to roughly 3nm per 1000ft. This is very easy to calculate in the air, regardless of airspeed.
Assuming your character’s destination is at sea level, or close enough that it doesn’t matter, he has to descend the entire 5000ft, which gives us 15nm.
If he is going to enter the traffic pattern (which is probably safer), he will want to arrive at the airport 1000ft above the ground, which means only 4000ft to descend, and 12nm.
If the airport isn’t near sea level, make the appropriate adjustments. For instance, if he’s flying to Denver, he would need to climb to reach the airport because at a mere 5000ft, he’s underground!
Regarding your follow-up comment about flying over water, pilots of single-engine piston planes usually remain within gliding distance of land for safety reasons, which will typically be about 1.5nm per 1000ft of altitude (or half the standard descent distance).

Typical decent(not including aerobatics and such) is a 3-6 degree slope regardless of aircraft, this is 300-650 feet per nautical mile. 5000feet above touchdown elevation thus yields 7.7 to 16.7NM
Power off glide distance for a C152 from 5000 with no wind would be about 6.5 NM, they have approx 8:1 glide ratio.
The weight of the aircraft will effect optimal speed, but their will be no significant effect on the decent angle or distance.
5000 feet above ground is generally reasonable for a C152. Service ceiling is about 14700 above sea level. (they are flying at 5000 feet plus the airport elevation. If the airport is 1500 feet above sea level then the airplane is cruising at 6,500 above sea level)


text:
Is using flaps the same as increasing the AOA?
The purpose of trailing edge flaps is to give the aircraft more lift at lower speeds.
But do simple flaps beneficent more than increasing the angle of attack?

The image looks like part of the wing just had it's angle of attack increased, and the other part did not.
Also considering flaps lower a wings critical angle of attack, and increasing the lift coefficient are they really just another way of changing the angle of attack?
If so why do smaller planes use them instead of setting up the landing gear to takeoff/land with greater angles of attack?

Not my area of expertise, but I think it doesn't really affect AoA so much. Instead the flaps (simple or complex) increase the curvature of the profile, and sometimes area, thus increasing lift.

The ultimate goal is to reduce the landing speed and takeoff run. Not to get the higher angle of attack. The speed without flaps would not be low enough even at higher critical AoA. The key is to generate the most lift as possible, with all means available.


text:
Is there a class E corridor in the class B north of San Diego International?
I am a relatively new pilot in the Los Angeles area and I have a question related to the Class B Airspace north of San Diego International, adjacent to Torrey Pines Glider Port.  The LA Terminal Map and Fore Flight show what appears to be a corridor or brake in the Class B Airspace. It shows the B Airspace to be 18 to 100, however there appears to be an altitude box just to the left of this area with an arrow pointing to the area in question that says floor of 18 to ceiling of 32 & floor of 68 to ceiling of 100.
My interpretation of this is that this box designates a Class E corridor just above 3,200' and just below 6,800'.
I have asked a number of pilots more experienced than myself and have received conflicting answers to my interpretation. Some agree and some do not.  I have attempted to find references online, but the only reference to a corridor in San Diego is the VFR corridor that overflies San Diego International above 3,300 and below 4,700 Northwest to Southeast.
I have attached a photo of the chart from Fore Flight for the area in question.  I would appreciate if someone who has flown this area could clarify this for me I would be very grateful as I don't want to bust B Airspace. Is my interpretation of the chart correct?  If not can someone explain to me what the box is saying?   Thank You.

I'm a frequent VFR owner/flyer in that area for past 12 years. The box is clearly identifying the floor within in the box it is pointing into.  That 1800/3200' is to keep transitioning aircraft either below or above the MIRAMAR MCAS departure corridor.  Aircraft that are inbound to Montgomery Field will often transition with a Class B clearance when flight followed by SoCal on 119.6, at 2500-3000'  Inbound commercial jets for Lindbergh Field will come thru that zone at 6800' and above. And yes, as depicted on the chart, offshore of Torrey Pines and west of the OCN 152 radial, the floor is 1800'.  If you're looking for a "corridor"to the South Bay onto Brown Field, you could fly the shoreline at 3600'-4600', from Del Mar, over Mt Soledad, and then join the VFR corridor over Lindbergh Field, and onto Brown Field.


text:
Is a holding pattern required on the Twentynine Palms VOR for RWY 26?
I am an instrument student and confused about whether or not you have to fly the holding pattern charted on the VOR RWY 26 at Twentynine Palms. At Jehli (Intermediate Fix), it says "No PT".

This chart provides two ways to begin the approach. The first is at the TNP VOR, which is labeled as an IAF (Initial Approach Fix). Since a holding pattern is charted, you are required to fly that holding pattern as part of the procedure if you begin at TNP.
The other way to begin the approach is at JEHLI, which is labeled as an IF (Intermediate Fix). The "NoPT" instruction only applies if you start the procedure at JEHLI, as this establishes you on the 255 inbound radial to TNP and no hold is needed.
If a hold or procedure turn is charted, you need to fly that maneuver unless you are coming from an IAF or IF with the "NoPT" instruction (or if ATC clears you "straight in").

Great, thanks a lot, very helpful

@Pondlife thanks, should have looked closer!


text:
Can a UAV over 55lbs legally fly 20 miles off the US coast?
For US aerospace companies that are developing UAVs heavier than 55lbs for application for the DOD, is it possible to test UAVs over the ocean outside what we would normally consider US controlled airspace legally without a FAA specific exemption?
I should add that in this particular case the UAV can be launched and recovered from Sea.
Thoughts?

There are already restricted airspaces inside the US airspace that the DoD uses to do their things (testing, training, that kind of fun stuff) in. But just for you to look at, this is the airspace that the US controls; it extends far or 20 miles off the coast for most of it and the parts where it does not, it is some other country's airspace.

Legal is more of a civilian term but this topic is more into the military scope, e.g. if things goes south it will be the military talking to you rather than FBI or PD, since when you are on a ship in the middle of the ocean you are quite possibly not bounded by the US laws anymore, but it's advisable to inform the relevant authority who are monitoring or using the airspace to avoid unnecessary trouble and conflict. Extreme example is when China shot a ICBM into Pacific in the 80s they had to inform every country to avoid WW3, but they did it anyway without giving a single thought of US laws.

There may be a difference between "what we would normally consider US controlled airspace" which is determined by UN (ICAO) international agreements and an area where US are sovereign. Such delegated areas include North Atlantic Oceanic Control Areas under responsibility of US/Canada/UK/France (cf. FIR viewer).

The United States does not own or control airspace outside its territorial limits, but there is an exception; our government has extended Class A airspace out to twelve miles from the coast of the contiguous 48 states and Alaska. If you launch the UAV at sea and stay out of US airspace, there's no need to ask for an exemption.


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What are the implications to consider when starting a university Flight Club?
I'm currently a University student in the United States, and finishing my PPL within the next two weeks (assuming I pass my checkride!)
Unfortunately, when I return to University for the Fall semester, there are zero flying resources. No local clubs, or anything of that nature. I am told by many of the pilots around my out of state flight school about their student flying clubs back in college, and it sounds amazing.
My University encourages students to start clubs, offering a maximum funding of $10,000 - $50,000. I presume because clubs increase the schools admission, it is worth the money for them? Being a large engineering school, I could see it being a selling point in tours.
My question is in three parts.

What are the implications of starting a student Flight/Aviators Club, and what benefits could it provide, outside of meeting new aviation friends? (Implications referring to expected safety precautions a school might want to impose, any FAA regulations pertinent to a club, and associations/partnerships we could create to show legitimacy to the school)
What would be a good way to find pilots within the University? (I'm sure out of 30,000 students there are some)
Would this be percieved by the general aviation community as "not my place" to start a student flying club, as I am a new pilot?

By "flying club" do you mean actually owning an airplane, or just a group of people interested in aviation?

Group of people, flying common destinations, etc.

If you aren't owning an airplane, then the "implications" are few. Just do it.

Not exactly the answer I was looking for :) Implications could concievably include rental agreements with local rental agencies, as well as safety requirements that may be required by an institution.

That is why it is a comment, not an answer... I guess it would help if I knew what you mean by "implications"? The first question is difficult to answer without knowing what you mean? Academic implications? Legal? Social?...

Edited with a deeper explanation of implications

It's difficult to answer this well. #1 depends at least partly on your school and its requirements for funding a club. #2 is more about publicizing a club in a university environment than about aviation. #3 is entirely subjective. I'd start with the AOPA resources and use them as a kind of checklist to make sure you've thought about everything. But you'll have to apply that to your own situation. You might also consider asking on academia.SE about general considerations around creating and publicizing school clubs.

The first rule of Flight Club is: "You don't talk about Flight Club", right?

Is the stated funding per year, one-time, or something else?  Is there a different amount for capital costs?  The school may be willing to spend more than its usual limit to buy a durable asset, which they could sell if the club failed, as long as the operating expenses (e.g. maintenance and insurance) fell within that budget.  They might even realize they could use said plane themselves to save other travel costs.

What are the implications of starting a student Flight/Aviators Club,
  and what benefits could it provide, outside of meeting new aviation
  friends? (Implications referring to expected safety precautions a
  school might want to impose, any FAA regulations pertinent to a club,
  and associations/partnerships we could create to show legitimacy to
  the school)

I was in college not all that long ago and I can speak to this a bit as I was involved in some clubs that built cars (Formula SAE) while not the same I see a lot of parallels. Generally speaking, and this is very university dependent but I have seen it apply across the board, if a school puts money towards a club the club must abide by the school's rules but more importantly it typically falls under their insurance policy. For something like a poetry club there is not that much risk, but when we were racing cars the university would inspect them all the time and there always had to be a faculty member present when we were running tests. We were lucky in that we had good faculty backing which is key, my advice here is to first find a professor (you are generally going to need an advisor anyway) that flies and get them excited about it and onboard as this will go a long way to help your case.
What gets tricky here is you flying on the university's dime. If you are not looking to buy a plane and you simply want to use the funds for rental that is an interesting predicament. An aviation lawyer may be able to answer better for you, but you need to confirm what the deal is with using club/org/university funding to rent and fly planes. Technically you are not getting compensated to fly but you are also not paying to fly while someone is paying for the aircraft (you are in turn paying 0 which is below your pro-rata share). If the students are splitting the rental costs, renting from a local FBO and are all checked out in the airframe you don't really need to even get the university involved.
There are universities like Embry-Riddle that are very aviation focused and offer training as a part of the curriculum so there are places that do it.
Getting a local flight school or FBO involved may help if you have a place to rent planes from and can guarantee business they may offer a small price break.
I would reach out to the National Intercollegiate Flying Association and see if they can offer any advice or help.

What would be a good way to find pilots within the University? (I'm
  sure out of 30,000 students there are some)

The airmen registry here in the US is public, you could always run it up against your school directory... I would ask around, post fliers etc. keep in mind that flying is not the cheapest hobby and college kids tend to not be all that cash liquid... I sure couldn't start flying until I had my first job.

Would this be percieved by the general aviation community as "not my
  place" to start a student flying club, as I am a new pilot?

IMO pilots are very receptive of other pilots. Old pilots love to inspire young pilots and you will most likely find a lot of support from them. GA awareness is never a bad thing either!

What are the implications of starting a student Flight/Aviators Club, and what benefits could it provide, outside of meeting new aviation friends? (Implications referring to expected safety precautions a school might want to impose, any FAA regulations pertinent to a club, and associations/partnerships we could create to show legitimacy to the school)

There really aren't any implications to starting a club. The FAA does not regulate clubs as long as you abide by the FAR's, especially with regards to cost sharing (which isn't as simple as the FAR makes it sound). As far as safety precautions the school would like, that is entirely up to the school administration, and you'll have to discuss it with them. It may be nothing, or it may be a non-starter, it depends.
You could also start a local EAA chapter, or host a WINGS event for currency training. There are also IFR clubs and you can work with a local flight school to offer things like ground courses. It is difficult to say what deals you can work out until you pick up the phone and do it. As far as legitimacy to your school, that is also specific to your institution and when you approach administration with your club idea they will set the terms.

What would be a good way to find pilots within the University? (I'm sure out of 30,000 students there are some)

The easiest way is probably to post fliers around the school in common areas. Don't limit yourself to licensed (or soon to be licensed) pilots though, invite anybody with an interest in aviation (or even drones/unmanned aircraft, which may be a bigger market at an engineering school). You can do a search on the FAA site for pilots, but it is a one-by-one search and going through your school roster would be a full time job for quite some time...

Would this be perceived by the general aviation community as "not my place" to start a student flying club, as I am a new pilot?

Absolutely not. When you spend more time around experienced pilots you will find that most are very welcoming to new pilots and are very much encouraged to do things like start clubs and attend meetings.

In regards to #2, what would be the purpose for non-pilot members? - as in, what could be offered to them. Being in a flight club without flying seems like a tease, but it would be great to somehow include potential pilots.

Believe it or not, there are quite a few members here, with high reputation, that are not pilots. Just because somebody isn't a pilot doesn't mean that they can't be interested in it. I'm assuming that a majority of your club actions will simply be meet-ups, tours of control towers or other ATC facilities, training, etc rather than actual flying.

For my terms of a Flight Club, the primary purpose would be flight

You are severely limiting your potential as a club then. Even full clubs do much more than just fly. I'm guessing that even though there are 30K-ish students, there may be 3-5 pilots...

@WillSimon You don't seem to know what you want to promote, to be honest. From my perspective, a general interest in aviation over many years is what led me into my PPL. I'd have definitely joined such a club, probably with the intention of training - but also to just meet likeminded people, attend airshows, events, ground school, engineering discussions, talks etc. I can imagine lots of people would be interested in a presentation from, say, a military pilot or an air traffic controller regardless of license


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Can briefly explain the principle behind the inversion on this power required curve?
I’ve noticed on several graphs in the “Advanced Pilot’s Flight Manual”, that power available is lower for any given speed at 10,000 feet as compared to sea level flight. The power required curves intersect at the sea level best rate-of-climb (BROC) speed. Can someone briefly explain why more power is required at 10,000 feet when below this BROC speed and less power is required at 10,000 feet when above it?

"Why is that?" -- why is what? There are at least three factual statements in your post, depending on how one parses it. Is there one in particular you are asking about? Are you asking for a broad discussion of the whole concept of Vy? Please edit your question to clarify what it is your question actually is.

Aaron, thanks for your input. I actually just finished CPL and started instructor ratings, and as I go I find there are more and more holes in my knowledge. When i was trained all I got was “more power”, “more nose down”. Not much theory during PPL/CPL.                                         All the questions I have are the ones he sent me to find in the books and many more, most I find in “FTGU” or “Advanced pilot” or online, but some I don’t..

@leha007: Oh, I'm sorry! I thought you had just finished PPL. Even more congratulations are in order! I can totally relate to what you are saying. When I first started helicopter training years ago, I asked my CFI if a certain book would be a good source of information. He told me that he'd seen it before and it was "way too much physics and math". He suggested that I find things with simpler, more functional information... I kept the book and changed the CFI.

Aaron yeah, most CFI’s are like that. I got the one that likes the theory. :)  that’s good though, I like learning.

You may be interesting about sections about the powercurve of How it flies

Power required is drag times speed. In essence, you ask why drag at the same lift and in 10,000 ft is growing either side of the best climb speed at sea level.
As @Kolom rightly points out, the coincidence of best climb speed at sea level being equal to lowest drag speed at 10,000 ft is just that, a coincidence. There is no causal relation.
The power required curve is shifted right due to lower density at 10,000 ft which requires the aircraft to fly faster for the same dynamic pressure. The X-axis of the plot is True Airspeed, so all polar points will shift right as altitude increases. Next, you will also note a small upward shift. This is caused by the lower Reynolds number at higher altitude which increases zero-lift drag at the same indicated speed.
The best rate of climb speed is where the local slopes of the power required and the power available curves match. Then the distance between both power curves  is greatest and leaves the highest specific excess power after the power required for steady flight has been subtracted from the available power. If the curves would be plotted over Indicated Airspeed, they would simply shift slightly up for the power required and down for the power available as density drops with increasing altitude. The author of your book chose to plot them over True Airspeed, so it might seem that the best ROC at sea level has some significance for the drag at 10,000 ft. It hasn't.
Please make sure you read the linked answers, too, because they should help to give more background. I have kept the answer short, so some things are not fully explained. For example, why there is a minimum drag point at all is explained at the target of the first link.

There is less drag on the aircraft at 10,000 feet. This means that the prop can drive the aircraft along at 120kts while moving less air than it would require at sea level. The trade-off is, when the plane is flying slowly at 10,000 feet, with a lot of drag due to the high angle of attack, the prop struggles to move enough air due to the low density of air molecules at altitude.

Thank you Aaron.


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Can the Master Caution illuminate without the System Annunciator Panel on the 737NG?
Does the master caution light illuminate only with the System Annunciator Panel?
Or is the master caution illumination also connected to the related system panels?
I mean if there is an indication on a system panel and the System Annunciator Panel is inop due to some issue, does the master caution illuminate alone?

If everything is working as designed then the Master Caution is always accompanied by one of the 12 annunciator lights (or more than 1, depending on the situation).
If things aren't working as designed, then what you'll see depends on the nature of the malfunction. If it's as simple as a burned-out bulb in the annunciator panel, then you could get the Master Caution without an accompanying light. That's usually followed by a disgruntled "oh, great" followed by heads swiveling around to find what individual amber light is illuminated. And/or pressing the Recall function (see what fails to light up, or comes on now), and/or using the Lights Test switch.

In the event of a bulb burning out (who is still using incandescents in safety-critical hardware?!) wouldn't the problem also be displayed on one of the MFDs?

@Dai: Incandescent bulbs can be quite reliable if they are used significantly below their maximum power rating.  LEDs are claimed to last longer, but I've seen plenty of LED assemblies with failed LEDs in them.

The 737 cockpit still uses the same 386 bulbs in the caution lights that the original ones did decades ago. And no, even the Max still doesn't have an EICAS.


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What is the hierarchy of aviation regulatory bodies?
What does the hierarchy of the aviation bodies look like?
Does it look like this:
International: ICAO
Continental: EASA,ECAC,...?
National:?

ICAO is organisation that draw "recommendations" for its members to use. Each country has control of its own airspace and surrounding area. EASA is a group of european countries so it is equal to national.

@vasin1987 I hope you don't mind that I built an answer around your comment.

@MichaelKjörling feel free. It is a fact (I hope!). I'm too lazy to format it.

As pointed out by vasin1987 in a comment to the question, each country's regulatory body has control of that country's airspace: These agencies exist in a "mesh" of coequals as opposed to a hierarchy.
The EASA is a EU agency and applies to all of EU, very similar to how the FAA is a US agency that applies to all of the US.
ICAO, in turn, deals primarily with situations where air traffic crosses regulatory borders. In its own words, borrowing from the page About ICAO on their web site,

The International Civil Aviation Organization (ICAO) is a UN specialized agency [which works] to reach consensus on international civil aviation Standards and Recommended Practices (SARPs) and policies[.]

Like pretty much the rest of the UN, the ICAO is more a forum for cooperation between regulatory bodies than a regulatory body in its own right.

Hum... ICAO coordinates the signature of treaties (list). Are you sure treaties don't have "force of law"? On the other hand, it's a side point, but EASA is not a ruling agency, each country in EU is sovereign. EASA directives are translated into local laws voted by local parliaments, which are the only elected bodies.

@mins Treaties have the force of law between the signing countries, and it is up to those signing countries to enact and enforce legislation for its citizens to abide by those treaties. If treaties themselves were law as it applied to citizens, we would get treaties as appendices to our FAR books. The mere act of signing a treaty doesn't enact legislation (laws), that comes later.

@RonBeyer. It seems this is a bit more complex: "In the United States, a different principle is established. Our constitution declares a treaty to be the law of the land. It is, consequently, to be regarded in courts of justice as equivalent to an act of the legislature, whenever it operates of itself, without the aid of any legislative provision" (source).

@mins Indeed it is, I think the key part of that is "whenever it operates of itself without the aid of any legislative provision...", probably a better question for law.se.

Mmm, so you could say the FAA and the EASA work on a continental scale? Are there more of these? Like an asian one? And what organizations work on a national scale and is there a layer deeper than that? And is the IATA anywhere to be found?

@Thepizzaguy "Mmm, so you could say the FAA and the EASA work on a continental scale?" No, "continent" is something quite different from "administrative division", "country" or "regulatory region".

@mins It's worth noting that the US government has a history of ignoring "inconvenient" provisions in our treaties (If one needs evidence of this look no further than our treaties with our indigenous peoples). We respect the provisions of treaties like the Chicago Convention facilitated through ICAO because we recognize tangible (economic) benefits from them, but we could also simply not implement provisions of the treaty in our regulatory structure…


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How was I able to just plug in my headphones and listen to ATC and pilot chatter?
I was travelling from Mumbai to Newark Liberty Intl on United Airlines 49, a Boeing  777-200. I was sitting in the economy section, last row, last seat to the plane's left, basically, I was literally the passenger on the last seat of the aircraft.
When I sat down, I plugged my earphones into the headphone jack and I could hear the conversation between ATC and the pilot, all I had to do was just twist the and hold the jack in a certain position. I could hear them talk to Mumbai ATC, the Islamabad ATC, Kabul ATC, even up to Iceland. My question is, how is this possible? What could have happened? Did the pilot or the airline know about this? Should I have told them about this? Is it illegal to listen to this chatter? Can this happen next time I travel or was I just lucky?

I faintly remember on (older) airliners where they don't have an Android-based entertainment system, the remote control allows you to select audio channels. One of the channels is the plane's ATC.

Yeah, that's the thing, I did not select any channels, it was just plug and play!

I'm so jelous, Channel 9 has been disappearing on United flights for years now. It's been a long time now since I was able to listen to it.

Are you certain you heard both sides of the conversation?  If you only heard the pilot, that can simply be radio-frequency-interference, the usually undesired effect of turning an audio device into an involuntary receiver for a nearby AM transmitter.  Fumbling with (rusty?) connections can give you a nonlinear junction useful for demodulating AM.  If you heard both sides of the conversation, though, it is more likely a service intentionally distributed in the cabin.

+1 for what Paul said. Basically anything with a diode inside of it, or an integrated circuit (since ICs have the so called body/substrate diodes) can act as a demodulator for AM. If the ratio between transmitter power and distance between the transmitter and receiver is good enough, you don't even  need a specifically tuned antenna.

Yup, I heard both sides of the conversation. I could hear the pilots greeting the Islamabad ATC by saying "Salam Walikum" or something like that, which was surprising given that they were Americans!

radio signals are broadcast through the air. it's not a secret that ANYONE can listen to them. so, of course you can, too.

Just wanted to add, it's not illegal! You can even tune in on some websites and listen; it's interesting to hear what goes on sometimes!

I remember once listening in while ATC repeatedly tried (and failed) to get the pilots of my plane to respond.  They finally contacted another plane from the same airline and asked them to let our pilots know ATC was trying to talk to them through some system with the airline.  I was wondering whether I should tell the flight attendants to let our pilots know that ATC wanted to talk to them...

This is a feature offered on some United Airlines aircraft and flights. It's an interesting way to hear what's going on in the cockpit. You can find lots of information by searching for United channel 9.

But, I did not switch to any channel at all, just plugged in my earphones and it worked! How's that possible?

It was left on channel 9 by the previous passenger.

And if you had to twist and hold the connector that just sounds like a bad connector.

Haha, it was my headphone jack and it's a UA flight. What more can we expect?

@Di437 There's no secrets in the communications between ATC and pilots. It's all freely broadcast, and if you have the correct equipment, you can listen in too. A easy way to do so is using the free website LiveATC (https://www.liveatc.net/). It's quite neat if you're curious, or into aviation as a hobby or profession.

@SnakeDoc except for in the UK, where the law still prevents me from listening in on it...

@Tim Well, you Euro's and your crazy laws ;-P Although, it seems, simply listening to LiveATC (the website) is not a violation of the law. If you setup radio equipment in your home to do so, then you would be. IANAL. In the US, and other sane parts of the world, you can listen to freely, and clearly transmitted radio signals so long as you don't broadcast without the appropriate license.

@Tim So, if a plane is flying from New York to Beijing over London, I can listen to conversations everywhere else, except London?

@Di437 If you're not a UK citizen, then you're not bound by UK laws unless you're in the UK. Being in UK airspace may make a slight difference, but in all practicality, you'll be just fine. It also seem to be consensus that if you're not the one with the radio equipment, you're not breaking any laws. So if you're on a flight such as this one, and it offers that "channel" over the entertainment system, you're in violation of no laws.

@Di437 If your plane from New York to Beijing is anywhere near London, the pilot is badly, badly lost.

@DavidRicherby LOL, I was expecting this reply to my comment from someone here. Did not disappoint! Yeah, don't read too much into the correctness in my poorly written analogy. It was there to just convey the point and I'm sure it did!

I remember that back in the 70's they had the United DC-10 "Friendship" and I could hear the pilots on channel 9.  We had engine problems and lost a lot of altitude and I heard them describing it all.  It was an odd feeling to look around and realize that none of the other passengers knew our pilot was freaking out until they got a restart.

Would Channel 9 be disabled in case of an emergency? To stop people panicking.

@JamesMundy From the ATC recordings I've heard of pilots working emergencies, I'd be significantly calmed by being able to hear them. Pilots and ATC tend to be cool as a cucumber when things are going wrong and it's quite impressive.

@pericynthion and the "previous passenger" was likely cabin crew, as they often sit in the very back row.

ATC and aircraft communications (at least in the US) are not restricted for receiving. Anyone can purchase (or make) an "Air band" receiver (or scanner radio) tunable through (roughly) 118-140 MHz and listen to ATC and aircraft communications.


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Do modern flights and pilots have reservations about flying over the Bermuda Triangle?
I know that the Triangle was pretty much legend back in the days but now, given that there is so much technology involved with respect to tracking and communications, do pilots, flights and airlines still have reservations about flying over this area? If so, why, and if not, are there regular flights/airlines that go over this route every day?

See http://travel.stackexchange.com/questions/89252/are-there-any-flights-which-fly-above-the-bermuda-triangle

It does appear that most of the major airlines avoid using flight 13, though

@TomMcW  That's for marketing to those who might be superstitious!  As for the Bermuda triangle, I've flown through it any number of times & that phrase has never even crossed my mind.  To say it's a "non-issue" would over-emphasize how much the notion of any Bermuda Triangle is even considered these days.

@RalphJ People that buy into the Bermuda Triangle myth have trouble getting a pilot's license. They can never get the great circles to line up properly on the flat earth

There is no evidence whatsoever that the "Bermuda triangle", which is not a thing, it's an entirely invented concept, is any different to any other part of the world.  Lloyds Shipping doesn't even rank it in the top 10 "risk" areas.

A quick check of a site like Flightradar24 will show that the area is not overly avoided. The triangle between the southern tip of Florida, Bermuda, and Puerto Rico has quite a bit of traffic.
The southern part is a busy route from Florida to Puerto Rico and other areas in the Caribbean. The rest is also part of routes from the east coast to the Caribbean and South America.
While the idea of an area causing mysterious disappearances is understandably popular, evidence suggests that the area has not been significantly more dangerous than other areas in the world. As noted, it's an important route between Florida and the Caribbean, and one would expect lots of traffic in this area, and therefore lots of incidents.
While navigation issues were once a not-infrequent cause of air incidents, modern technology has made this sort of thing much more rare. Airline flights are monitored by ATC. Anomalies in either magnetic bearings or radio aids such as VOR or GPS are routinely surveyed and listed on navigation charts. I took a quick look and nothing seemed to stand out here. Weather forecasting has also become much more helpful with the usage of long range weather radar and weather satellites.
A look at incidents in this area shows most incidents were in the 1960s or earlier. The few recent air incidents seem to be nothing out of the ordinary. General aviation accidents are fairly common (flying into a level 6 thunderstorm also not advised), and airliners divert due to technical issues fairly frequently.
While some people may have apprehensions about the area, this concern doesn't seem to be supported by a higher than normal rate of incidents and the area is routinely traveled by both ships and aircraft.

From Flightradar24.com
Don't worry about that question mark, I'm sure it's totally routine, nothing to see here

I like the comment on the question mark, I was going to comment on it and just before I started typing a response, I saw your comment. Thanks, but my other question remains, what do pilots flying over this route think? Do they like it, do they want to avoid it?

@Di437 That is rather opinionated, and off-topic for this site. One pilot might think its another trip to Puerto Rico and the next wears a tinfoil hat the entire way. Some may avoid it, others couldn't care less.

I read your comment about the question mark and spent 3 minutes looking for it!

I have flown in that area numerous times and it never concerned me in the slightest.  Just an antiquated myth...

I flew a C172 into the Bermuda Triangle (Bimini) with my family aboard on my Commercial license qualifying flight in 1976 and never gave a thought to the supposed "danger" flying there.


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How does an airline pilot log P1U/S time under EASA regulations?
I am looking for the exact way to log P1 Under Supervision (P1U/S) time for Commercial Airline Pilots (FOs).
I know as a fact that, as a Pilot Flying first officer, you can log up to 500 hours in P1U/S which are counted as PIC time towards unfreezing the ATPL (must be countersigned by the captain).
However, I am not sure if I need to also log the SIC time in the same entry of the logbook (same flight)? Where can I find the exact regulation about this?